This paper explains the PAPER method for measuring the EoR power spectrum. While some experiments plan on subtracting foregrounds, PAPER will stick to uncontaminated regions of power spectrum space. Narrow field simulations had previously expected this region to have little dependence on baseline length. This paper explains why in the wide-field case, foreground contamination gets worse with baseline length.
The PAPER strategy is to avoid this regime by concentrating sensitivity in a very dense array but sample longer spectral modes. In all this results in a comparitively lower SNR measurement (see right) but with better understood noise.